/* 共有リンクの受け皿。アプリ名とボタン1つだけ (docs/decisions.md 49章)。 */
:root {
  color-scheme: light dark;
  --ground: #eef0f4;
  --text: #1f2430;
  --accent: #3b6fe0;
  --on-accent: #ffffff;
}
@media (prefers-color-scheme: dark) {
  :root {
    --ground: #1c1f26;
    --text: #e8eaf0;
    --accent: #6f95f0;
    --on-accent: #10131a;
  }
}
* { box-sizing: border-box; }
html, body { margin: 0; height: 100%; }
body {
  background: var(--ground);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", sans-serif;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 16px;
}
main {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 28px;
  width: 100%;
  max-width: 360px;
}
h1 { margin: 0; font-size: 1.6rem; font-weight: 700; }
.button {
  display: block;
  width: 100%;
  padding: 16px;
  border-radius: 14px;
  background: var(--accent);
  color: var(--on-accent);
  font-size: 1.1rem;
  font-weight: 600;
  text-align: center;
  text-decoration: none;
}